CLAIM OF PRIORITYThis application is a continuation of, and claims priority to, U.S. application Ser. No. 14/542,353 entitled “TECHNIQUES FOR DATA RETENTION,” filed Nov. 14, 2014, now U.S. Pat. No. 10,628,387 with an issue date of Apr. 21, 2020, which is related to, and claims priority to provisional utility application No. 61/905,460 entitled “FIELD HISTORY RETENTION,” filed Nov. 18, 2013; provisional utility application No. 61/904,822 entitled “SCALABLE OBJECTS,” filed on Nov. 15, 2013; provisional utility application No. 61/904,826 entitled “MULTI-TENANCY FOR A NOSQL DATABASE,” filed Nov. 15, 2013; provisional utility application No. 61/905,439 entitled “BIG OBJECTS,” filed Nov. 18, 2013; and provisional utility application No. 61/905,457 entitled “ORCHESTRATION BETWEEN TWO MULTI-TENANT DATABASES,” filed Nov. 18, 2013, the entire contents of which are all incorporated herein by reference.
TECHNICAL FIELDEmbodiments relate to techniques for storage and management of data. More particularly, embodiments relate to selectively retaining data based on preselected characteristics.
BACKGROUNDRelational databases are commonly used to store large amounts of data. Current relational database systems have limits beyond which the system does not scale well. Thus, environments in which large amount of data must be managed (e.g., on-demand services environments, multitenant database environments, electronic commerce, logistics) may near or reach conditions in which the relational database becomes less effective. Accordingly, current relational database management systems are not ideal in some situations.
BRIEF DESCRIPTION OF THE DRAWINGSEmbodiments of the invention are illustrated by way of example, and not by way of limitation, in the figures of the accompanying drawings in which like reference numerals refer to similar elements.
FIG. 1 is a block diagram of one embodiment of an architecture that may provide data retention as described herein.
FIG. 2 is a flow diagram of one embodiment of a technique for transferring data from a relational database environment to a non-relational database environment.
FIG. 3 is an interaction diagram of one embodiment of a technique for querying a non-relational (NoSQL) database using relational database (SQL) commands.
FIG. 4 is a block diagram of one environment wherein an on-demand database service might be used.
FIG. 5 is a block diagram of one embodiment of elements of environment ofFIG. 4 and various possible interconnections between these elements.
DETAILED DESCRIPTIONIn the following description, numerous specific details are set forth. However, embodiments of the invention may be practiced without these specific details. In other instances, well-known circuits, structures and techniques have not been shown in detail in order not to obscure the understanding of this description.
As discussed above, there are conditions and/or situations in which a relational database system is being used to manage large amounts of data that does not require the functionality of a relational database system, but is related to data that does. The examples that follow are presented in terms of field history and field history archives; however, the techniques described herein are not limited to these examples.
When records are edited or modified in a relational database environment, entries corresponding to the change can be made. For example, an initial account record may be:
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| Account ID | Account Name | Expected Value |
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| 123456789 | Acme, Inc. | $1,000,000 |
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The account record can then me modified, for example, to:
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| Account ID | Account Name | Expected Value |
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| 123456789 | Acme Systems, Inc. | $2,000,000 |
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The corresponding field history information can be maintained in another table:
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| Field History ID | Parent ID | Old Value | New Value |
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| 0000000001 | 123456789 | Acme, Inc. | Acme Systems, Inc. |
| 000000002 | 123456789 | $1,000,000 | $2,000,000 |
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In this simplified example, for each column in the original object that is changed a row is generated in the history table. The history table can be useful for keeping an audit trail, for example
With an active environment, the history can grow to a very large number of rows quickly. However, because the data is static after creation and the data is not frequently accessed, the features and flexibility provided by a relational database system may be unused. Thus, a different, more scalable database structure can be utilized for these types of data.
In one embodiment, this type of information can be stored on a non-relational database, for example, Apache HBase, which is an open source non-relational distributed database. Other databases can also be supported. In one embodiment, a JAVA® Database Connectivity (JDBC) driver can be utilized to support low-latency SQL queries to run over the data stored in the non-relational database (e.g., HBase).
A non-relational database can provide better horizontal scalability than a relational database model and provide linear access characteristics, and simpler read and write semantics. In one embodiment, one or more HBase databases can be integrated into a platform (e.g., salesforce) using a framework or interface (e.g., External Objects in salesforce) that allows for data from external sources to be utilized in the platform. In one embodiment, the framework/interface allows for the external database/resource to appear to a user as if it were a part of the platform.
In one embodiment, transfer of data from the relational database environment to the non-relational database environment is not continuous. Transfer of data can occur in response to a request and/or in response to a set of one or more preselected conditions, which can include, for example, exceeding a threshold number of rows in a table, exceeding a threshold database size, and/or available bandwidth. Other conditions can also be used.
In one embodiment, the techniques described herein are provided within a multitenant database environment. Within a multitenant database environment, the conditions that trigger transfer or data and/or the format of the data may vary from tenant to tenant. In one embodiment, each tenant of the multitenant database can have a custom interface that can be utilized to access information in the relational database environment as well as the non-relational database environment.
In one embodiment, the functionality described herein operates to provide a query agent with a JDBC application programming interface (API) from the perspective of a client device. The query agent operates to translate a SQL query (e.g., passed through as a string in the JDBC API) into a series of “native” NoSQL store APIs. In one embodiment, the API to the NoSQL store is at a lower level, so the techniques described herein allow a higher-level query language (e.g., SQL) to be used to read/write data and manage schemas. Various architectures are provided in the description that follows.
FIG. 1 is a block diagram of one embodiment of an architecture that may provide data retention as described herein. In one embodiment, client devices are used by one or more users to access services from a service provider. The service provided can be, for example, an on-demand services environment, a multitenant database environment, or any other type of service provider.
Client devices110 and115 operate to allow a user to access remote services provided byservice provider140 vianetwork130.Client devices110 can be, for example, desktop computers, laptop computers, tablets, smart phones, thin clients, etc. Network130 can be any network, for example, the Internet, a corporate local area network or wide area network, a cellular network, and/or any combination thereof.
Service provider140 can be any number of servers and/or other devices that operate to provide services to one or more client devices. In one embodiment,service provider140 operates with one or more relational databases (e.g.,150) and one or more non-relational databases (e.g.,160).Service provider140 operates usingrelational database150 and non-relational database160 as described above.
In one embodiment,service provider140 is an on-demand services environment with multiple client organizations that provides different and/or different levels of services to the client organizations. For example,service provider140 can be a multitenant database environment that provides custom interfaces and data isolation to the different client organizations. In the example, multitenant database environment, the transfer of data fromrelational database150 and non-relational database160 can be on an organization-by-organization basis with different parameters and/or conditions for different organizations.
FIG. 2 is a flow diagram of one embodiment of a technique for transferring data from a relational database environment to a non-relational database environment. Data to be moved from the relational database environment to the non-relational database environment is identified,210. Various parameters and conditions are used to determine what data is to be moved/copied/transferred.
In a multitenant database example, not all organizations/tenants may have the functionality to copy data from the relational database to the non-relational database as described. That is, the functionality may be provided on a tenant-by-tenant basis. Further, the fields and/or data that can be copied can be limited/determined/etc. on a tenant-by-tenant basis. In one embodiment, the data to be copied for a particular tenant is based on a key prefix and/or date (e.g., field history, older than a specified date).
The selected data is copied from the relational database to the non-relational database,220. In one embodiment, a message is enqueued with the parameters (e.g., field history, older than a specified date) for the data to be copied. In one embodiment, the message is used to handle copying of the data in batches. For example, when a chunk of rows has been processed, the message (or a variation) is enqueued again to handle the next chunk of rows until all of the specified data has been copied.
In one embodiment, a chunk of data to be copied is delineated by a data range and an offset. The offset is used to prevent re-loading of rows that have already been copied. In one embodiment, when the selected data has been copied, a message handler marks the current job as successful and can insert a row in the source table to help track what data has been copied. Data can then be deleted from the relational database.
Access to the copied data is then provided with a common user interface,230, so that the user has access to the copied data that is stored in the non-relational database environment. In one embodiment, the interface providing access to the relational database environment also includes virtual entity or other interface to the non-relational database to allow the user seamless access to data copied from the relational database environment to the non-relational database environment.
In contrast to turning SQL queries into batch-oriented map/reduce jobs, the techniques described herein can be utilized to transform the SQL queries into a set of HBase (or other non-relational database) scans that can be executed in parallel for each row key range. In one embodiment, these scans are executed in parallel for each row key range and can be combined to provide results of the query. As a result, the latency of the queries is low enough to allow data to drive analytic-type queries over large amounts of data. In one embodiment, all this is hidden behind a JDBC driver. In one embodiment, the user provides a schema for their database table data and a SQL query. In one embodiment, column values can be mapped to individual KeyValues and/or combined together in a single KeyValue to reduce the size of data, which can improve read speed.
FIG. 3 is an interaction diagram of one embodiment of a technique for querying a non-relational (NoSQL) database using relational database (SQL) commands. In one embodiment, the technique ofFIG. 3 is performed within a multitenant database environment.
SQL interface310 is any type of interface/client device that can be used to receive SQL commands and provide results form the SQL commands. For example,SQL interface310 can be a SQL application running on a client computing device. SQL-to-NoSQL agent320 provides the functionality described herein. SQL-to-NoSQL agent320 may be a centralized single agent or can be distributed over multiple entities.Non-relational database330 can be any type of non-relational database, for example, HBase.
In response to receiving at least one SQL command representing a query,SQL interface310 sends the query,350, to SQL-to-NoSQL agent320. In response to receiving the SQL command, SQL-to-NoSQL agent320 parses the query,352. SQL-to-NoSQL agent320 then compiles a query, which can include retrieving metadata,354, fromnon-relational database330. The query plan can be optimized,356. In one embodiment the SQL query is transformed into one or more scans that are relatively simple, for example, with no joins, basic filtering and/or simple aggregation.
In one embodiment, the scans can be run on a sub-section of tables so that not all tables need to be replicated in the non-relational database. In some embodiments, the results need only be approximately correct. Other optimizations can be utilized to provide the desired level of performance.
The query plan can be executed as multiple parallel scans,360, ofnon-relational database330. In one embodiment, a set of HBase (or other non-relational database) scans that can be executed in parallel for each row key range. In one embodiment, these scans are executed in parallel for each row key range and can be combined to provide results of the query.
In one embodiment,non-relational database330 can perform filtering and/or aggregation. Results of the multiple parallel scans are returned,365, to SQL-to-NoSQL agent320. In one embodiment, SQL-to-NoSQL agent320 can perform merge sorting on the results. By combining the results of the one or more scans, the system can provide an aggregated/unified result to the original SQL query. The results are provided,370, toSQL interface310.
In one embodiment, deletion from the relational database environment is decoupled from the copy process. In embodiment, a system job in the relational database environment periodically (e.g., daily, weekly, 12 hours) runs to query tenants/organizations that have the functionality described herein enabled to determine whether any data copy jobs have been completed. If so, the data that has been copied to the non-relational database environment may be deleted from the relational database environment.
In one embodiment, when a deletion message/job is processed, the handler determines the parameters (e.g., field history, older than a specified date) for the deletion request. In one embodiment, this is accomplished with a system-level job. It can, for example, run a query to find all organizations that have post-archival deletion enabled and have post-archival deletion requests that have not been processed. In one embodiment, the system-level job can enqueue a message for each combination. In one embodiment, other job types (e.g., an organization-level job) can be utilized to process deletions.
The non-relational database can be queried to determine the data within the specified range. For each chunk, the handler passes identifiers loaded from the non-relational database environment to the relational database environment to cause a hard delete of the corresponding rows from the relational database environment. Loading the identifiers from the non-relational database environment to the relational database environment ensures that data will not be deleted before being successfully copied from the relational database environment to the non-relational database environment.
FIG. 4 illustrates a block diagram of anenvironment410 wherein an on-demand database service might be used.Environment410 may includeuser systems412,network414,system416,processor system417,application platform418,network interface420,tenant data storage422,system data storage424,program code426, andprocess space428. In other embodiments,environment410 may not have all of the components listed and/or may have other elements instead of, or in addition to, those listed above.
Environment410 is an environment in which an on-demand database service exists.User system412 may be any machine or system that is used by a user to access a database user system. For example, any ofuser systems412 can be a handheld computing device, a mobile phone, a laptop computer, a work station, and/or a network of computing devices. As illustrated in hereinFIG. 4 (and in more detail inFIG. 5)user systems412 might interact via anetwork414 with an on-demand database service, which issystem416.
An on-demand database service, such assystem416, is a database system that is made available to outside users that do not need to necessarily be concerned with building and/or maintaining the database system, but instead may be available for their use when the users need the database system (e.g., on the demand of the users). Some on-demand database services may store information from one or more tenants stored into tables of a common database image to form a multi-tenant database system (MTS). Accordingly, “on-demand database service416” and “system416” will be used interchangeably herein. A database image may include one or more database objects. A relational database management system (RDMS) or the equivalent may execute storage and retrieval of information against the database object(s).Application platform418 may be a framework that allows the applications ofsystem416 to run, such as the hardware and/or software, e.g., the operating system. In an embodiment, on-demand database service416 may include anapplication platform418 that enables creation, managing and executing one or more applications developed by the provider of the on-demand database service, users accessing the on-demand database service viauser systems412, or third party application developers accessing the on-demand database service viauser systems412.
The users ofuser systems412 may differ in their respective capacities, and the capacity of aparticular user system412 might be entirely determined by permissions (permission levels) for the current user. For example, where a salesperson is using aparticular user system412 to interact withsystem416, that user system has the capacities allotted to that salesperson. However, while an administrator is using that user system to interact withsystem416, that user system has the capacities allotted to that administrator. In systems with a hierarchical role model, users at one permission level may have access to applications, data, and database information accessible by a lower permission level user, but may not have access to certain applications, database information, and data accessible by a user at a higher permission level. Thus, different users will have different capabilities with regard to accessing and modifying application and database information, depending on a user's security or permission level.
Network414 is any network or combination of networks of devices that communicate with one another. For example,network414 can be any one or any combination of a LAN (local area network), WAN (wide area network), telephone network, wireless network, point-to-point network, star network, token ring network, hub network, or other appropriate configuration. As the most common type of computer network in current use is a TCP/IP (Transfer Control Protocol and Internet Protocol) network, such as the global internetwork of networks often referred to as the “Internet” with a capital “I,” that network will be used in many of the examples herein. However, it should be understood that the networks that one or more implementations might use are not so limited, although TCP/IP is a frequently implemented protocol.
User systems412 might communicate withsystem416 using TCP/IP and, at a higher network level, use other common Internet protocols to communicate, such as HTTP, FTP, AFS, WAP, etc. In an example where HTTP is used,user system412 might include an HTTP client commonly referred to as a “browser” for sending and receiving HTTP messages to and from an HTTP server atsystem416. Such an HTTP server might be implemented as the sole network interface betweensystem416 andnetwork414, but other techniques might be used as well or instead. In some implementations, the interface betweensystem416 andnetwork414 includes load sharing functionality, such as round-robin HTTP request distributors to balance loads and distribute incoming HTTP requests evenly over a plurality of servers. At least as for the users that are accessing that server, each of the plurality of servers has access to the MTS' data; however, other alternative configurations may be used instead.
In one embodiment,system416, shown inFIG. 4, implements a web-based customer relationship management (CRM) system. For example, in one embodiment,system416 includes application servers configured to implement and execute CRM software applications as well as provide related data, code, forms, webpages and other information to and fromuser systems412 and to store to, and retrieve from, a database system related data, objects, and Webpage content. With a multi-tenant system, data for multiple tenants may be stored in the same physical database object, however, tenant data typically is arranged so that data of one tenant is kept logically separate from that of other tenants so that one tenant does not have access to another tenant's data, unless such data is expressly shared. In certain embodiments,system416 implements applications other than, or in addition to, a CRM application. For example,system416 may provide tenant access to multiple hosted (standard and custom) applications, including a CRM application. User (or third party developer) applications, which may or may not include CRM, may be supported by theapplication platform418, which manages creation, storage of the applications into one or more database objects and executing of the applications in a virtual machine in the process space of thesystem416.
One arrangement for elements ofsystem416 is shown inFIG. 4, including anetwork interface420,application platform418,tenant data storage422 fortenant data423,system data storage424 forsystem data425 accessible tosystem416 and possibly multiple tenants,program code426 for implementing various functions ofsystem416, and aprocess space428 for executing MTS system processes and tenant-specific processes, such as running applications as part of an application hosting service. Additional processes that may execute onsystem416 include database indexing processes.
Several elements in the system shown inFIG. 4 include conventional, well-known elements that are explained only briefly here. For example, eachuser system412 could include a desktop personal computer, workstation, laptop, PDA, cell phone, or any wireless access protocol (WAP) enabled device or any other computing device capable of interfacing directly or indirectly to the Internet or other network connection.User system412 typically runs an HTTP client, e.g., a browsing program, such as Microsoft's Internet Explorer browser, Netscape's Navigator browser, Opera's browser, or a WAP-enabled browser in the case of a cell phone, PDA or other wireless device, or the like, allowing a user (e.g., subscriber of the multi-tenant database system) ofuser system412 to access, process and view information, pages and applications available to it fromsystem416 overnetwork414. Eachuser system412 also typically includes one or more user interface devices, such as a keyboard, a mouse, trackball, touch pad, touch screen, pen or the like, for interacting with a graphical user interface (GUI) provided by the browser on a display (e.g., a monitor screen, LCD display, etc.) in conjunction with pages, forms, applications and other information provided bysystem416 or other systems or servers. For example, the user interface device can be used to access data and applications hosted bysystem416, and to perform searches on stored data, and otherwise allow a user to interact with various GUI pages that may be presented to a user. As discussed above, embodiments are suitable for use with the Internet, which refers to a specific global internetwork of networks. However, it should be understood that other networks can be used instead of the Internet, such as an intranet, an extranet, a virtual private network (VPN), a non-TCP/IP based network, any LAN or WAN or the like.
According to one embodiment, eachuser system412 and all of its components are operator configurable using applications, such as a browser, including computer code run using a central processing unit such as an Intel Pentium® processor or the like. Similarly, system416 (and additional instances of an MTS, where more than one is present) and all of their components might be operator configurable using application(s) including computer code to run using a central processing unit such asprocessor system417, which may include an Intel Pentium® processor or the like, and/or multiple processor units. A computer program product embodiment includes a machine-readable storage medium (media) having instructions stored thereon/in which can be used to program a computer to perform any of the processes of the embodiments described herein. Computer code for operating and configuringsystem416 to intercommunicate and to process webpages, applications and other data and media content as described herein are preferably downloaded and stored on a hard disk, but the entire program code, or portions thereof, may also be stored in any other volatile or non-volatile memory medium or device as is well known, such as a ROM or RAM, or provided on any media capable of storing program code, such as any type of rotating media including floppy disks, optical discs, digital versatile disk (DVD), compact disk (CD), microdrive, and magneto-optical disks, and magnetic or optical cards, nanosystems (including molecular memory ICs), or any type of media or device suitable for storing instructions and/or data. Additionally, the entire program code, or portions thereof, may be transmitted and downloaded from a software source over a transmission medium, e.g., over the Internet, or from another server, as is well known, or transmitted over any other conventional network connection as is well known (e.g., extranet, VPN, LAN, etc.) using any communication medium and protocols (e.g., TCP/IP, HTTP, HTTPS, Ethernet, etc.) as are well known. It will also be appreciated that computer code for implementing embodiments can be implemented in any programming language that can be executed on a client system and/or server or server system such as, for example, C, C++, HTML, any other markup language, Java™, JavaScript, ActiveX, any other scripting language, such as VBScript, and many other programming languages as are well known may be used. (Java™ is a trademark of Sun Microsystems, Inc.).
According to one embodiment, eachsystem416 is configured to provide webpages, forms, applications, data and media content to user (client)systems412 to support the access byuser systems412 as tenants ofsystem416. As such,system416 provides security mechanisms to keep each tenant's data separate unless the data is shared. If more than one MTS is used, they may be located in close proximity to one another (e.g., in a server farm located in a single building or campus), or they may be distributed at locations remote from one another (e.g., one or more servers located in city A and one or more servers located in city B). As used herein, each MTS could include one or more logically and/or physically connected servers distributed locally or across one or more geographic locations. Additionally, the term “server” is meant to include a computer system, including processing hardware and process space(s), and an associated storage system and database application (e.g., OODBMS or RDBMS) as is well known in the art. It should also be understood that “server system” and “server” are often used interchangeably herein. Similarly, the database object described herein can be implemented as single databases, a distributed database, a collection of distributed databases, a database with redundant online or offline backups or other redundancies, etc., and might include a distributed database or storage network and associated processing intelligence.
FIG. 5 also illustratesenvironment410. However, inFIG. 5 elements ofsystem416 and various interconnections in an embodiment are further illustrated.FIG. 5 shows thatuser system412 may includeprocessor system412A,memory system412B,input system412C, andoutput system412D.FIG. 5 showsnetwork414 andsystem416.FIG. 5 also shows thatsystem416 may includetenant data storage422,tenant data423,system data storage424,system data425, User Interface (UI)530, Application Program Interface (API)532, PL/SOQL534, saveroutines536,application setup mechanism538, applications servers5001-400N,system process space502,tenant process spaces504, tenantmanagement process space510,tenant storage area512,user storage514, andapplication metadata516. In other embodiments,environment410 may not have the same elements as those listed above and/or may have other elements instead of, or in addition to, those listed above.
User system412,network414,system416,tenant data storage422, andsystem data storage424 were discussed above inFIG. 4. Regardinguser system412,processor system412A may be any combination of one or more processors.Memory system412B may be any combination of one or more memory devices, short term, and/or long term memory.Input system412C may be any combination of input devices, such as one or more keyboards, mice, trackballs, scanners, cameras, and/or interfaces to networks.Output system412D may be any combination of output devices, such as one or more monitors, printers, and/or interfaces to networks. As shown byFIG. 5,system416 may include a network interface420 (ofFIG. 4) implemented as a set ofHTTP application servers500, anapplication platform418,tenant data storage422, andsystem data storage424. Also shown issystem process space502, including individualtenant process spaces504 and a tenantmanagement process space510. Eachapplication server500 may be configured to tenantdata storage422 and thetenant data423 therein, andsystem data storage424 and thesystem data425 therein to serve requests ofuser systems412. Thetenant data423 might be divided into individualtenant storage areas512, which can be either a physical arrangement and/or a logical arrangement of data. Within eachtenant storage area512,user storage514 andapplication metadata516 might be similarly allocated for each user. For example, a copy of a user's most recently used (MRU) items might be stored touser storage514. Similarly, a copy of MRU items for an entire organization that is a tenant might be stored to tenantstorage area512. AUI530 provides a user interface and anAPI532 provides an application programmer interface tosystem416 resident processes to users and/or developers atuser systems412. The tenant data and the system data may be stored in various databases, such as one or more Oracle™ databases.
Application platform418 includes anapplication setup mechanism538 that supports application developers' creation and management of applications, which may be saved as metadata intotenant data storage422 by saveroutines536 for execution by subscribers as one or moretenant process spaces504 managed bytenant management process510 for example. Invocations to such applications may be coded using PL/SOQL534 that provides a programming language style interface extension toAPI532. A detailed description of some PL/SOQL language embodiments is discussed in commonly owned U.S. Pat. No. 7,730,478 entitled, “Method and System for Allowing Access to Developed Applicants via a Multi-Tenant Database On-Demand Database Service”, issued Jun. 1, 2010 to Craig Weissman, which is incorporated in its entirety herein for all purposes. Invocations to applications may be detected by one or more system processes, which manage retrievingapplication metadata516 for the subscriber making the invocation and executing the metadata as an application in a virtual machine.
Eachapplication server500 may be communicably coupled to database systems, e.g., having access tosystem data425 andtenant data423, via a different network connection. For example, oneapplication server5001might be coupled via the network414 (e.g., the Internet), anotherapplication server500N−1might be coupled via a direct network link, and anotherapplication server500Nmight be coupled by yet a different network connection. Transfer Control Protocol and Internet Protocol (TCP/IP) are typical protocols for communicating betweenapplication servers500 and the database system. However, it will be apparent to one skilled in the art that other transport protocols may be used to optimize the system depending on the network interconnect used.
In certain embodiments, eachapplication server500 is configured to handle requests for any user associated with any organization that is a tenant. Because it is desirable to be able to add and remove application servers from the server pool at any time for any reason, there is preferably no server affinity for a user and/or organization to aspecific application server500. In one embodiment, therefore, an interface system implementing a load balancing function (e.g., an F5 Big-IP load balancer) is communicably coupled between theapplication servers500 and theuser systems412 to distribute requests to theapplication servers500. In one embodiment, the load balancer uses a least connections algorithm to route user requests to theapplication servers500. Other examples of load balancing algorithms, such as round robin and observed response time, also can be used. For example, in certain embodiments, three consecutive requests from the same user could hit threedifferent application servers500, and three requests from different users could hit thesame application server500. In this manner,system416 is multi-tenant, whereinsystem416 handles storage of, and access to, different objects, data and applications across disparate users and organizations.
As an example of storage, one tenant might be a company that employs a sales force where each salesperson usessystem416 to manage their sales process. Thus, a user might maintain contact data, leads data, customer follow-up data, performance data, goals and progress data, etc., all applicable to that user's personal sales process (e.g., in tenant data storage422). In an example of a MTS arrangement, since all of the data and the applications to access, view, modify, report, transmit, calculate, etc., can be maintained and accessed by a user system having nothing more than network access, the user can manage his or her sales efforts and cycles from any of many different user systems. For example, if a salesperson is visiting a customer and the customer has Internet access in their lobby, the salesperson can obtain critical updates as to that customer while waiting for the customer to arrive in the lobby.
While each user's data might be separate from other users' data regardless of the employers of each user, some data might be organization-wide data shared or accessible by a plurality of users or all of the users for a given organization that is a tenant. Thus, there might be some data structures managed bysystem416 that are allocated at the tenant level while other data structures might be managed at the user level. Because an MTS might support multiple tenants including possible competitors, the MTS should have security protocols that keep data, applications, and application use separate. Also, because many tenants may opt for access to an MTS rather than maintain their own system, redundancy, up-time, and backup are additional functions that may be implemented in the MTS. In addition to user-specific data and tenant specific data,system416 might also maintain system level data usable by multiple tenants or other data. Such system level data might include industry reports, news, postings, and the like that are sharable among tenants.
In certain embodiments, user systems412 (which may be client systems) communicate withapplication servers500 to request and update system-level and tenant-level data fromsystem416 that may require sending one or more queries to tenantdata storage422 and/orsystem data storage424. System416 (e.g., anapplication server500 in system416) automatically generates one or more SQL statements (e.g., one or more SQL queries) that are designed to access the desired information.System data storage424 may generate query plans to access the requested data from the database.
Each database can generally be viewed as a collection of objects, such as a set of logical tables, containing data fitted into predefined categories. A “table” is one representation of a data object, and may be used herein to simplify the conceptual description of objects and custom objects. It should be understood that “table” and “object” may be used interchangeably herein. Each table generally contains one or more data categories logically arranged as columns or fields in a viewable schema. Each row or record of a table contains an instance of data for each category defined by the fields. For example, a CRM database may include a table that describes a customer with fields for basic contact information such as name, address, phone number, fax number, etc. Another table might describe a purchase order, including fields for information such as customer, product, sale price, date, etc. In some multi-tenant database systems, standard entity tables might be provided for use by all tenants. For CRM database applications, such standard entities might include tables for Account, Contact, Lead, and Opportunity data, each containing pre-defined fields. It should be understood that the word “entity” may also be used interchangeably herein with “object” and “table”.
In some multi-tenant database systems, tenants may be allowed to create and store custom objects, or they may be allowed to customize standard entities or objects, for example by creating custom fields for standard objects, including custom index fields. U.S. patent application Ser. No. 10/817,161, filed Apr. 2, 2004, entitled “Custom Entities and Fields in a Multi-Tenant Database System”, and which is hereby incorporated herein by reference, teaches systems and methods for creating custom objects as well as customizing standard objects in a multi-tenant database system. In certain embodiments, for example, all custom entity data rows are stored in a single multi-tenant physical table, which may contain multiple logical tables per organization. It is transparent to customers that their multiple “tables” are in fact stored in one large table or that their data may be stored in the same table as the data of other customers.
Reference in the specification to “one embodiment” or “an embodiment” means that a particular feature, structure, or characteristic described in connection with the embodiment is included in at least one embodiment of the invention. The appearances of the phrase “in one embodiment” in various places in the specification are not necessarily all referring to the same embodiment.
While the invention has been described in terms of several embodiments, those skilled in the art will recognize that the invention is not limited to the embodiments described, but can be practiced with modification and alteration within the spirit and scope of the appended claims. The description is thus to be regarded as illustrative instead of limiting.